1. Field
The following description relates to a small optical system mounted in a portable terminal apparatus.
2. Description of Related Art
A camera module is mounted within a portable terminal. The camera module includes an optical system and an image sensor. The optical system includes a plurality of lenses, and the image sensor includes a plurality of sensor devices that convert optical signals into electrical signals.
An optimal performance of the optical system and the image sensor is needed in order to improve performance of the camera module. However, in the camera module mounted in the portable terminal, performance of the optical system and the image sensor is not easily improved due to spatial limitations of the portable terminal. As an example, it is difficult to increase a size of the image sensor of the camera module to produce a high-resolution camera module. Therefore, an optical system having a wide field of view and having an overall focal length (F) number of 2.0 or less to produce a high-resolution camera module is desired to be developed.